[petsc-users] is TS_EQ_DAE_SEMI_EXPLICIT_INDEX functional

[Jed Brown]

I believe this is intended to work with most any implicit solver,
*provided* the initial conditions are compatible.  It was added by Emil,
but I don't see it explicitly tested in PETSc.

"Huck, Moritz via petsc-users" <petsc-users at mcs.anl.gov> writes:

> Hi,
> TS_EQ_DAE_SEMI_EXPLICIT_INDEX(?) are defined in TSEquationType but not mentioned in the manual.
> Is this feature functional ?
> If yes how do I have to define the RHSFunction? 
> (I am asking since the ODE variant has it defined as G= M^-1 g, which cannot work for a DAE)
>
> Best Regards,
> Moritz